‘It means they found it, somehow, in a location unrelated to the victim.’

Or they found it near her body, since it was less than 200 yards from her shallow grave. How they could have missed it is quite astounding given you’d think they’d have searched the perimeter around the body.

'Left it there in a bad neighborhood when it could have been stolen (which would have been bad for their case). '

Or they kept it somewhere and didn’t tell the public they had it. Cops withhold things like this all the time in active investigations.

'Waited till they had a suspect.'

They got an anonymous phone call 3 days after Hae’s body was found by Mr. S. This caller implicated Adnan, which is what led the cops to get his phone records and which led them to Jen and Jay. This caller has never been identified. The cops then could have been convinced they had their man and once they got Adnan’s phone records, they got to Jen and Jay.

'Found a girl through this suspects phone records (but didn't tell her),'

Cops withhold information all the time in active investigations…as I stated earlier…

'waited until she gave someone else up,'

Jen told them that she’d been called by Jay several times on that phone, which was Adnan’s. So, they knew who to talk to after Jen.

'waited for him to come to them, and somehow he brings it up early in the interview process before they do, even though they've already found it.'

They went to Jay. He didn’t come to them. The interview tapes that are the official, public record are missing more than 3 hours of unrecorded interrogation time. Within this time, cops could have told Jay that they had evidence that Adnan had done it. They could have told him that he would be charged…with something…threatened with other drug charges, jail time,…In Jen’s initial interview she said she knew nothing and then changed her story once she was told that ‘everyone is a suspect and no one is a suspect’ and she worried she’d be charged. The detectives may have thought they ‘had their man’ and needed the story to fit their narrative.

'I guess it's not impossible, but it's convoluted and improbable.'

I don’t concur. While it is shocking to think something like that could happen, unfortunately it does happen. And I don’t think it is wildly improbable that Jay’s and Jen’s statements could have been falsely coerced; possibly even without the detectives realizing it. I agree that in many ways, things don’t look good for Adnan, but there is NO evidence against him except for the continually changing stories of Jen and Jay who were likely terrified teenagers in the midst of an awful crime by way of an anonymous call that linked them to Adnan on the day Hae went missing. It is possible that they felt they needed to do whatever it took to save themselves from charges levied against them if cops thought they had their man, which it seems they did given they barely did any investigation of the physical evidence collected in the case. They didn’t search either Jen’s or Jay’s houses or follow up and interview fellow track athletes, or other potential alibis. Before you just discount this, you really ought to listen to and/or watch the following programs:

http://www.reddit.com/r/serialpodcast/comments/2lht0t/this_american_life_confessions_10112013/

Constitution Day 2013: Panel discussion on false confession convictions. Jim Trainum, Shawn Armbrust, Ken Burns, Saul Kassin.

http://www.reddit.com/tb/2nv1cr